We have developed a battery of specific polyclonal antisera in rabbits against various synthethic peptides from the mature region and the latency associated protein (LAP) region of TGF-Betas 1 through 5. Each of the antisera against a given TGF-Beta has a different spectrum of specificities and can be useful in one or more of the following assays: Western immunoblots, immunoprecipitation of metabolically labeled material, radioimmunoassays, and immunohistochemical staining. None of these antisera has proven useful in neutralizing the biological activity of TGF-Betas. We have also developed polyclonal antisera against native TGF-Betas 1 and 2 in rabbits and turkeys that are useful in neutralizing the receptor binding and biological activity of TGF-Betas 1 and 2, and that collectively have allowed the specific detection and/or quantitation of TGF-Beta1 and TGF-Beta2 by radioimmunoassays, Western immunoblots, immunoprecipitation of metabolically labeled material, radioreceptor assays, growth inhibition assays, and sandwich enzyme-linked immunosorbent assays. However, none of these antibodies have been useful in immunohistochemical staining of TGF-Betas I and 2. Among the various mentioned assays for quantitation of TGF-Beta1 and TGF-Beta2, the sandwich enzyme-linked immunosorbent assays, each of which uses both turkey and rabbit neutralizing antibodies, are the methods of choice for specific, sensitive, precise and rapid measurements of TGF-Beta1 and TGF-Beta2 in complex biological fluids.